Epson S1C63558 4.4 Input Ports (K00–K03and K10–K13), 4.4.1 Configuration of input ports, 4.4.2 Interrupt function, Kxx, Data bus

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Input Ports)

4.4 Input Ports (K00–K03 and K10–K13)

4.4.1 Configuration of input ports

The S1C63558 has eight bits general-purpose input ports. Each of the input port terminals (K00–K03, K10–K13) provides internal pull-up resistor. Pull-up resistor can be selected for each bit with the mask option.

Figure 4.4.1.1 shows the configuration of input port.

Kxx

VDD

Interrupt

request busData

Address

VSS

Mask option

Fig. 4.4.1.1 Configuration of input port

Selection of "With pull-up resistor" with the mask option suits input from the push switch, key matrix, and so forth. When "Gate direct" is selected, the port can be used for slide switch input and interfacing with other LSIs.

4.4.2 Interrupt function

All eight bits of the input ports (K00–K03, K10–K13) provide the interrupt function. The conditions for issuing an interrupt can be set by the software. Further, whether to mask the interrupt function can be selected by the software.

Figure 4.4.2.1 shows the configuration of K00–K03 (K10–K13) interrupt circuit.

K00, 10

Data bus

Address
	Address
Input comparison
register (KCP00, 10)	Interrupt factor	Interrupt
	flag (IK0, 1)
		request
Address
Interrupt selection	Interrupt mask
register (SIK00, 10)	register (EIK0, 1)
Address		Address

K01, 11

K02, 12

K03, 13

Fig. 4.4.2.1 Input interrupt circuit configuration

28 EPSON S1C63558 TECHNICAL MANUAL